/*
 *  Copyright 2009 Advanced Industrial Science and Technology (AIST).
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

/*! \file
 *  \brief
 */
#pragma once

#include <thrust/graph/detail/out_edge_iterator.hpp>

#include <thrust/detail/device/dereference.h>
#include <thrust/iterator/iterator_traits.h>

namespace thrust {

template <typename OutEdgeIter
          , typename VertexDescriptor
          , typename EdgeDescriptor
          , typename CalledSpace>
struct out_edge_iter;

template <typename InEdgeIter
          , typename VertexDescriptor
          , typename EdgeDescriptor
          , typename CalledSpace>
struct in_edge_iter;
  
namespace detail {

struct out_edge_iter_friend {
  
  template <typename OutEdgeIter
            , typename VertexDescriptor
            , typename EdgeDescriptor
            , typename CalledSpace>
  static inline __device__
  typename device::dereference_result<out_edge_iter<
                                        OutEdgeIter
                                        , VertexDescriptor
                                        , EdgeDescriptor
                                        , CalledSpace
                                        > >::type
  dereference( const out_edge_iter<
               OutEdgeIter
               , VertexDescriptor
               , EdgeDescriptor
               , CalledSpace>& iter)
  {
    return iter.dereference( thrust::called_from_device_tag());
  }

};

struct in_edge_iter_friend {
  
  template <typename InEdgeIter
            , typename VertexDescriptor
            , typename EdgeDescriptor
            , typename CalledSpace>
  static inline __device__
  typename device::dereference_result< in_edge_iter<
                                         InEdgeIter
                                         , VertexDescriptor
                                         , EdgeDescriptor
                                         , CalledSpace
                                         > >::type
  dereference( const in_edge_iter<
               InEdgeIter
               , VertexDescriptor
               , EdgeDescriptor
               , CalledSpace>& iter)
  {
    return iter.dereference( thrust::called_from_device_tag());
  }
  
};

namespace device {

template<typename OutEdgeIter
         , typename VertexDescriptor
         , typename EdgeDescriptor
         , typename CalledSpace>
struct dereference_result< out_edge_iter<OutEdgeIter
                                         , VertexDescriptor
                                         , EdgeDescriptor
                                         , CalledSpace> >
{
  typedef typename thrust::iterator_traits< out_edge_iter<OutEdgeIter
                                                          , VertexDescriptor
                                                          , EdgeDescriptor
                                                          , CalledSpace> >::reference type;
};  
  
template <typename InEdgeIter
          , typename VertexDescriptor
          , typename EdgeDescriptor
          , typename CalledSpace>
struct dereference_result< in_edge_iter<InEdgeIter
                                        , VertexDescriptor
                                        , EdgeDescriptor
                                        , CalledSpace> >
{
  typedef typename thrust::iterator_traits< in_edge_iter<InEdgeIter
                                                         , VertexDescriptor
                                                         , EdgeDescriptor
                                                         , CalledSpace> >::reference type;
};


template<typename OutEdgeIter
         , typename VertexDescriptor
         , typename EdgeDescriptor
         , typename CalledSpace>
inline __device__
typename dereference_result< out_edge_iter<
                               OutEdgeIter
                               , VertexDescriptor
                               , EdgeDescriptor
                               , CalledSpace> >::type
dereference( const out_edge_iter<
             OutEdgeIter
             , VertexDescriptor
             , EdgeDescriptor
             , CalledSpace
             >& iter)
{
  return out_edge_iter_friend::dereference( iter);
}
  
template <typename InEdgeIter
          , typename VertexDescriptor
          , typename EdgeDescriptor
          , typename CalledSpace>
inline __device__
typename dereference_result< in_edge_iter<
                               InEdgeIter
                               , VertexDescriptor
                               , EdgeDescriptor
                               , CalledSpace> >::type
dereference( const in_edge_iter<
             InEdgeIter
             , VertexDescriptor
             , EdgeDescriptor
             , CalledSpace> & iter)
{
  return in_edge_iter_friend::dereference( iter);
}
  
} // end namespace device
  
} // end namespace detail

} // end namespace thrust
